Continuous gauging apparatus



March 31, 1953 M. A. CROSBY 2,632,956

CONTINUOUS GAUGING APPARATUS Original Filed Jan. 5, 1947 2 SHEETS-SHEET l INVENTOR giYELvlN A CROSBY m a ma/mi,

2 TORNEYS March 31, 1953 v M. A. CROSBY CONTINUOUS GAUGING APPARATUS Original Filed Jan. 5, 1947 2 SHEETS-SHEET 2 88 7 u so 54 86 INVENT ATTORNEYS Patented Mar. 31, 1953 2,632,956 y CONTINUOUS GAUGINGAPPARATUS Y Melvin A. Crosby, CincinnatL Ohio, assignor to The Commonwealth Engineering Company of Ohio, Dayton, Ohio, a corporation of Ohio Original application January 5, .1947, SerialNo.

724,319. Divided and this app ication Decemher-14, 1949, Serial No. 132,894

, 1 This invention relates to machine tools, and particularly to an indicating mechanism for machine tools for assisting the operator in themeduction of workpieces of the correct size and shape. I

' This application is a division of my co pending application Serial No. 724,319, filed January 5, 1947.

' Heretofore, for an operator to produce a workpiece of a predetermined configuration on a machine tool, it was necessary for him to measure the workpiece with gaging instruments from time to time, and to compare his measurements with a part print or other record.

Another method often employed for producing workpieces was to have the machine fitted with contouring controls so that the workpieces produced were automatically sized by the machine according to a template or pattern, or whatever other type of control was employed with the machine. In this latter case, a machine having a great deal of special equipment is required, and a set-up of this nature isnot only costly, but the change from one workpiece to another involves considerable skill and time. 7

Having the foregoing in mind, the particular object of the instant invention is to provide an inexpensive arrangement adapted for being mounted on a standard machine tool, such as a lathe, whereby accurately sized workpieces can be produced in a minimum of timeand at small cost.

Another object is to provide mechanism in combination with a lathe or other machine tool whereby a continuous indication is given of the workpiece'size throughout the cutting operation.

Still another object is the provision of amaehine tool havinga quite inexpensive indicating device associated therewith for giving a visual indication wheneverthe workpiece is above or below a predetermined size.

These and other objects and advantages will become more apparent upon reference to the following description taken in connection with the accompanying drawings, in which:

Figure 1 is a fragmentary side view of a machine tool such as a lathe equipped according to this invention;

Figure 2 is a transverse section indicated by line 2-'-2 on Figure 1 and showing more in detail the detecting and indicating mechanism of this invention;

Figure 3 is a perspective view showing a typical template adapted for being utilized with the detecting and indicating mechanism of this invention; v j y Figure 4 is a longitudinal section through the feeler arm support as indicated by lin 4 -4 on Figure 2; and

5 Claims. (ores-r74) Figure 5' is an enlarged detail view showing the construction of the switch for the indicating means and the manner in which it is actuated.

Referring to the drawings somewhatmore in detail, there is shown in Figures 1 and 2 a machine tool such as a lathe having a bed In, a headstock l2, and a tailstock [4. A tool supportingcarriage I6 is reciprocableon bed 10 in the usual manner. The headstock may comprise workpiece holding means, such as a chuck|8 that supports workpiece so that it can be driven in rotation relative to cutting tool 22 that is carried on compound 24 mounted on cross slid 25 of carriage l6. 7

According to this invention, and as will be seen in Figure 2, carriage l6 supports a longitudinally adjustable slide 28 on which is mounted a column member 30. At the upper end of member 30 is a pivot pin 32 and pivotally mounted on pin 32 i amount of movement of contact 46 in either di- 7 is a feeler arm 34. Feeler arm 34 may advantageously include the detachable connection at 36 so that the 'end of the feeler arm which engages the workpiece can be replaced by'one of a difierent configuration or length, if desired.

Slide 28 is supported on a base member and these parts are dovetailed together as indicated at 82. A screw 84 is held against axial movement in base member 80 by the handwheel 86 and collar 88. Nut on slide 28 engages screw 84so rotation of the screw by the handwheel 86 results in adjustment of the slide on the base member. Column 30 includes a vertically extending sleeve part 38 through which extends plunger 40. The upper end of plunger 40 bears on the bottom of an arm 42 that is pivoted on the previously mentioned pivot pin 32. Mounted on top of arm 42 is a limit switch 44 having a movable contact 46 pivoted at 53 and two fixed contacts 48 and Si! arranged on opposite sides thereof. Movable contact 46 is spring biased in one direction (in the clockwise direction as shown in Fig. 5) by a torsion spring 52 and is adapted for being moved inthe other directionby plunger 54 extending upwardly from the limit switch and abutting the lower end of adjustable screw 55 carried in a projecting fingerportion 58 forming a part of feeler arm 34. Contact 46 and contacts 48 and 50 are connected in circuit with a source of electrical energy, Such as battery 60,and the undersize and oversize indicating lamps B2 and 64; It will be apparent that when contact 46 is held in the position shown in Figures 2 and 5, neither of the said lamps will be lighted but a predetermined rection from its center position will cause one or the other of the said lamps to become lighted to give a visual indication to the machine operator Qt re ati e mqvem nt tween a m 4.? and 4- The actual spacing oi contact 48 from contacts 48 and a is, of course, very small and is exage gerated in the drawings for the sake, of clarity.

For actuating plunger 40, thereby to bring about movements of arm 42 to follow feeler arm 34 when the workpiece being turned is the correct size, there may be a template 66 carried on the bed of the machine, as illustrated in Figure 2 A typical template is shown inFigureBj and. will be seen to comprise the contoured upper portion 68 along which plunger 40 rides.

In operation, when the workpiece being turned is the correct size, arms 34 and 42 will move in unison as the feeler arm follows the workpiece, and the plunger 40 follows surface 68 of thetemplate and contact will accordingly remain spaced from both contacts 48 and 50 so. that neither of Lamps 62. or 64 will light; 7 However, it the workpiece departs from the correct. sizeiethen. there. will? he a differential movement between. arms 3d and t2 which will, in turn, bring about relative movement between switch. East and. screw 53'. which will cause. contact 45; to/clcse on, one as: the other of contacts 48 and. as, thereby to. illuminate one of lamps a: 6,4. The. one. of the lamps. illuminated. will indicate to. the operator whether. the. workpiece is at that-moment undersi'ze. or oversize, and he make an adjustment in. the tool setting.v to compensate for the particular ofi size condition indicated.

Ere-m. the foregoing, it. will be. evident that. th-isinvention is adapted for use either asa; siniple; indicating device as illustrated, or in con.- neotion. with machine. tools having automatic contouring, devices. associated therewith. In the lastemcntioned case;v the detecting. and indicating device according, to. this. invention. is: highly useful because itwill immediately detect. and indicate'tool Wear orother' faults, in the. ma,- chine organization. which cause imperieotly sized workpiecesv ta be. produced, even though the. automatic contouring controls were working perfectly,

It be understoodthat this invention. suseeptibleta modification; in order tov adaptit try different usages and: conditions; and; accordmam. is desired to comprehend such modifications; within. this. invention as may fall, within the: scope oh the appended claims.

, Lola-inn 1 A; size indicating device for a mashing. tool comprising: a, feeler arnr having one. end pivotally supported. and. its? other end adaptedt'for, bearing on a; workpiece: heingmachined; a. support for the one: end of the; arm, a: plungerrreoi-procable on. said support;..saict plunger'being'adaptsed to bear on a templatev at one: end,. a. switch pivoted on saidcsupport' on the: sameaxis. said f'eeler armand bearingiorr the othen'end of. saidplunger, and means; on said: arm for actuating said switch upon: relative'movementhetweem said pin and having" its end adapted for engagement.

with the workpiece on said axis, aswitclr pivotallysupported on said pin having actuating member in engagement with said arm whereby relativemovement hetweerrsaid armand switch will actuate the latten a plunger reciprocabfe 4 on said column and bearing at one end on said switch, and astationarily mounted. template engaging the other end of said plunger.

3. A size indicating device for a machine tool comprising: a column adapted for being mounted on the tool support of a machine tool for movement with the support in a direction parallel to the work axis of the machine, a pivot pin in the upper endof' the column, an arm pivoted on said pin and having its end adapted for engagement with the workpiece on said axis, a. switch pivotally supported on said pin having an actuating member in engagement with said arm whereby relative movement between said arm and switch will actuate the latter, a plunger reciprocable on said column and bearing at one end on said switch, a. stationarily mounted, template engaging the other end. of said. plunger,. and. meansf'er adjustingf said column. on said. support in a. direction parallel. to said] work axis.

41 In a size indicating device for a machine tool; a support adapted. for mounting on the tool carriage of av machine. tool for movement therewith in a directionparallel to the work axis of the machine, a pivot. pin. in the endv oi the support, a pair of arms pivoted on said pin and one being, adapted for engagement with a work-piece on said. axis, a. switch on the other arm having an actuating. member in engagement with said one arm so di'i'lferer'iti'al' movement between said arms will actuate said switch, a. stationary template, aplunger bearing. between said. template and the said other arm, and a-pairofli'ghts. connected incircuit with. said. switch andadapted for being selectively illuminated thereby upon a predetermihed difierential movement between said arms in either. direction from a. given relative. position. ofi'said arms.

5. In a size. indicating; device. for use with a. machine tool;. a support adaptedfor being mounted to move alongtthe work axisof the machine. with. the cutting. means thereof, a feeler arm. pivoted on saidsupp'ort and having an end adapted. for engaging a workpiece being. machinedso. as to he movable relative to. the support in. conformity with the, contour of the workpiecebein-g' shaped, a template adaptedfo-r beingv mounted stationary relative to the work-piece, a member: movably uided on the support and engaging; said. templateto be actuated. by the contour thereof when. the supportand template move relatively, a second armpivoted on said support onthe same axis as said feeler arm: and engaging said member to be. moved. thereby as said member is moved bythe tem-plat e and electricalvmeans arranged so. as to be. sensitive'solely to relative pivoting movements of. saidarms for indicating departures incontour ofv the workpiece from that. designated-bysaid template.

' MELVIN- A. CROSBY.

REFERENCES' CITED The following references are of record in thefile of. this patent:

Warner Dec. 30, 

